brcmfmac: add support for SAE authentication offload

The firmware may have SAE authentication code built-in. This is
detected by the driver and indicated in the wiphy features flags.
User-space can use this flag to determine whether or not to provide
the password material for SAE authentication in the nl80211 CONNECT
command.

Signed-off-by: Chung-Hsien Hsu <stanley.hsu@cypress.com>
Signed-off-by: Chi-Hsien Lin <chi-hsien.lin@cypress.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>